This invention relates to an industrial robot usuable in factory automation and others.
Some robots have an arm and a hand carried on an end of the arm. Motors drive the arm and vary the position of the hand. The weight of the arm causes loads on the motors which vary as a function of the position or angle of the arm. Therefore, the weight of the arm tends to adversely affect the control of the position of the hand. As suggested from the above description, the weight of the arm, that is, the gravity, adversely affects various controls of the robot.